Private Mode
When I access certain web sites in Private Mode, the browser delays about 4 seconds before loading the web site, but when using Firefox in regular mode, the web site loads normally. I notice this only with some non-https web sites (http).
This does not happen with other browsers; for example, Incognito Mode in Chrome does not have this issue.
I have tested Firefox on numerous installations both old and new on numerous PCs, and it always does this.
What is the problem? Is it a bug in Firefox or an anomaly with the way some non-https web sites interact with Firefox?
Alla svar (7)
You can check the timing in the Network Monitor.
Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem.
- switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
- do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window
Problem still happens in troubleshoot mode. Have also tried this on another PC with a fresh install, and still has the problem.
Can you post a link to a publicly accessible page (i.e. no authentication or signing on required)?
Are those websites possibly using local storage (indexedDB) as that might be disabled in PB mode ?
Here are the sites. These sites are all mine, so I can answer any questions about them.
Load these in Firefox Private Mode to see the loading delay.
This site loads quickly, no problem: https://gator1.tech/
This is the same web site content as above, but has the 4 second delay problem: http://damondb.org/
Here are 2 more test sites that also have the delay problem: http://fortunadb.org/ and http://fortunadb.net/
both of these have about 4 second delay when accessing with Firefox in Private Mode.
The above web sites are just HTML/CSS no databases, content management systems, etc.
fortunadb.org and fortunadb.net are just simple single-HTML page sites.
The other thing I notice is that I have never seen the delay problem with https sites, only http sites (no secure server).